Tool for truing shafts.



P. SCHON.

TOOL FOR TRUNG SHAFTS. APPLICATION FILED JUNE 18, 1911.

Patented Aug. 13,1918.

tlme. 30

PIERRE SCI-ION, OF DETROIT, MICHIGAN.

TOOL FOR TRUING- SHAETS.

Specification of Letters Patent. Patented Aug. 13,1918.

Application filed June 18, 1917. Serial No. 175,455.

To'aZZ whom it may concern: Y

Be it known that I, -PIE-RRE ScHoN, a sub ject of Marie Adelaide, Grand Duchess of Luxemburg, and a resident of Detroit, in the county of Wayne and State of Michigan, haveinvented certain new and useful Improvements in Tools for Truing Shafts, of which the following is a specification.

The present invention relates to a tool for truing crank shafts of internal combustion engines, air compressors, pumps, steam engines, and all other shafts which are subjected to uneven wear, due to lateral thrust, and the like, while in operation.

It is well known that the crank shaft pins of steam and internal combustion engines, and the like types of mechanism, are'subjected to uneven wear due to variance in pressure exerted upon the shaft, particularly with internal combustion engines where the wear is greatest at the bearing contact. When the crank shaft is thus unevenly worn, it is difficult, and practically impossible, to obtain the proper adjustment of the connecting rod bearings, and it is-the practice to remove the crank shaft from the motor and regrind it on a special machine. This operation is costly, and consumes a great deal of Special cutting tools have also been used in an attempt to true the crank shaft without removing the same from the motor, but are impractical, owing to difficulty in. adjusting them to maintain t e required even pressure of the jaws on the crank shaft during a full revolution of the latter, to prevent digging in at the high points, and to clamp on the crank shaft when of relatively small diameter.

It is, therefore, an object of the present in vention to provide a tool which will remove all high points on a crank shaft, and which may be trued by merely removing the ordinary oil pan of a motor, the connecting rod or rods, and the bearings, and clamping the tool on the shaft without removing the latter from the motor.

Briefly stated, the invention comprises a tool aving a main jaw for engagement against one side of the crank shaft, and an anchoring jaw adapted to encircle the opposite side of the crankshaft, and being adj ustably and yieldably connected to the main jaw. A cutter is removably mounted in the main jaw and normally urged out of contact with the adjacent side 'of the crank shaft,

and a connection is providedbetween the movably mounted tool and the opposed an-.

choring jaw for maintaining substantially an equi-distance between the anchoring jaw and the cutter so that'the latter' will not work against the depressed I side of the crank shaft or pin. The invention also embodies a. peculiar form of main jaw to retain the latter from following depressions in the sides of the crank shaft, and to thus insure the uniform cutting or grinding of the same.

The above,'and various other objects and I this invention will be in part advantages of part understood, from the described, and in following detailed description of the present preferred embodiment, the same being illustrated in the accompanying drawing,"

wherein:

Figurel is a longitudinal view of a tool constructed according to the present invention, and as applied to a. crank shaft, the View showing the tool partly in elevation and partly in section.

Fig. 2 is a transverse section through the same taken substantially on the plane indicated by the line 22 on Fig.1, and looking in the direction of the jaws.

Fig. 3 is a similar view taken substantially pin the plane indicated by the line 33 of Referring to this drawing, 10 designates the main jaw which is in the form of a block relatively fiat and elongated and provided at opposite ends with recesses or grooves 11, and provided at its inner side with a trans versely extending flat walled recess 12, the opposed walls 13 of which incline or flare outwardly. The inner wall of the recess 12 is interrupted by a transversely extend-ing slot 14 formed in the inner face of the jaw 10, the slot 14 being relatively deep and being offset toward one of the end walls 13 of the recess. a

The jaw 10 is provided upon its outer end exterior enlargement 16 at its base portion adjoining the jaw 10 to outwardly facing shoulder. A longitudinally extending slot 17 is formed in one side of the annular enlargement 16 and opens through the said shoulder of the'enlargearcuate in form with the extremities thereof with a tubular shank 15' having an annular provide an annular l of the shank.

' reduce frictional contact therebetween.

enlarged and forked or slotted at their outer sides. Tlfe jaw 18 is substantially S8111icylindrical in form and adapted to engage about one side of a crank shaft A, and to hold the opposite side of the crank shaft against the opposed inclined. faces 13 of the main jaw. The jaw 18 has a fiat portion at its middle to receive the r ank shaft A. thereagainst, and which, when the tool is assembled, is equi-distantly spaced from the contacting portions of the walls 13 with the crank shaft to center the latter and to space the ends of the jaw 18 from the shaft and headed ends of the jaw 18 are transversely apertured, which apertures aline in the opposite sides of the forked ends of the jaw.

A connecting sleeve 19 surrounds the base end of the shank 15, and is held from turning there-about by the provision of a set screw 20 which is threaded through one side of the bushing 19 and engages in the slot 17 The screw 20 holds the bushing or sleeve ldfrom turning upon the shank, and at the same 'ti'lne;adinits of the longitudinal movement. of the members relatively to each other. The base end of the sleeve 19, or the end adjacent to the main jaw 10, is provided with a connecting plate 21 preferably of a length and width corresponding to that of the main jaw 10, and which is provided at opposite ends with slots or recesses forming pairs of spaced-apart lugs 22 at the opposite ends of the connecting plate. j

Pivotally mounted upon transverse cross pins 23 in the forked heads of the connecting jaw 18, is a pair of opposed latch-bolts 24, the free ends of which are provided with transversely extending key heads 25 adapted to engage over the upper faces of the lugs 22, and to seat in recesses 26 formed in transverse alinenient across the outer sides of the lugs. The latch-bolts 24 are of a length greater than that of the depth of the main jaw 10, and the connecting plate 21' and the connecting jaw 18 are adapted to alternately move toward and from the opposite faces of the jaw 10.

The tool is provided with a handle 27, the same being of cylindrical form, and being relatively long. The base end of the handle 27 is enlarged and internally screw-tln'eaded for screw-tln-cznled engagement over the connecting sleeve 19 to firmly connect the handle 27 to the connecting jaw 18. lt-will be noted from Fig. 1 that the screw-tln'eaded portions of the handle 27 and the connecting sleeve 19 are relatively long so that the handle may be adjusted into various positions longitudinally upon the connecting sleeve. The handle 27 is provided, internally, with an annular shoulder 28 arranged intermediate the ends of the handle and facingtoward the base end ,thereof. The

The.

arranged about the shank 15 about the shouldered portion 16 thereof, the spring 30 engaging at one end agalnst said shoulder and at its opposite end against the adjacent side of a bushing 31, seated against the shoulder 28 of-the handle. The spring 80 thus normally urges the shank 15 and the main jaw 10 toward the crank shaft A. Longitudinal adjustment of the handle 27 upon the connecting sleeve 19 varies the pressure of the spring 30 against the jaw as compared with the pressure of the jaw 18 against the opposite side of the crank shaft A. The desired gripping adjustment of the jaws 10 and 18 may therefore be ob taincd by turning the handle 27 in either direction.

A knife or cutter cutting edge 33 centered in the recess 12 of the jaw and adapted to engage the adjacent portion of the crank shaft A. The cutter 32 is of less depth than that of the slot 14, and is adapted for adjustment longitudinally therein. The cutter 32 is provided at its outer face with an internally threaded opening adapted-to receive the stem 3% of a cutter stem 35, the stud 34 being externally screw-threaded and adapted to fit in the opening in the cutter 32. The cutter stem is longitudinally slidable through the main jaw 10, and its shank 15, the stem 35 projecting outwardly to a considerable extent beyond the end of the shank. An annulus 36 is fixed upon the outer end of the stem 35, and a helical spring 37 surrounds the stem 35 between t 1e annulus 36 and the adjacent end of the shank 15. The spring 37 normally urges the cutter stem 35 and the cutter 32 outwardly away from the crank shaft A.

The connecting jaw unit comprises the connecting jaw 18 with its links 24, the connecting plate 21 and the sleeve '19, and the handle 27 with the parts carried thereby. The handle 27 is also provided with an internally threaded bushing 38 arranged in the outer end of the handle against the shoulder 29, and through which is threaded a connecting screw 39 which is seated and centered at its inner end in the outer end of the cutter stem 35. The screw 39 connects the cutter to the connecting jaw unit, and adjusts the jaw toward and from the, cutter 32. The outer end of the adjusting} is seated in the I transverse slot 14 of the jaw 10 and has its screw 39 is provided with a transversely apertured head 40 adapted to receive a pin or the like therethrough to hold in the turning of the screw 39 for advancing and retracting the knife or cutter 32 with respect to the crank shaft A.

In operation, the handle 27 is turned in a direction to release the pressure of the spring 30 from the shoulder portion 16 of the main jaw shank. This adjustment relaxes the pressure upon the connecting plate 21 and the key-headed latches 24 may be readily disengaged from the lugs 22 and swung out of the' slots '11 of the main jaw. The main jaw 10 is now applied to acrank shaft with the inclined faces of the main jaw engaging the exterior surface of the crank shaft A at spaced-apart points. The arcuate connecting jaw 18 is now engaged about the opposite side of the crank shaft A and'the connecting bolts 2 1 are replaced in the slots 11 and engaged over the lugs 22.

The handle 27 is now turned in an opposite direction to increase the tension upon the spring 30 and urge themain jaw 10 against the crank shaft A. The recess 12 is ofgreater depth than the projecting adjacent side of the crank shaft A so that the cutter 32 may be retracted into the recess and out of contact with, the crank shaft.

When the desired tension is placed upon the jaws 10 and 18, the adjusting screw 39 may be turned through the bushing 38 to advance the stem 35 against the tension of the spring 37. In this manner, the knife or cutter 32 is moved into the desired position relatively to the crank shaft.

The opposed walls or faces 13 of the main jaw 10 hold the crank shaft from following the knife or cutter 32 into the recess 12 when a depressed side of the crank shaft A is presented to the cutter. In such instance, the cutting edge 33 is held from contact 1 with the crank shaft, and only engages the same at thehigh points.

The crank shaft may be readily ground by the use of this tool without removing the crank shaft from the engine or other machine. It is only necessary to remove the bearing portions of the connecting rod and to apply the tool of this invention to the crank pin from beneath the motor, or other machine, and to turn the crank shaft by hand or otherwise with the tool of this invention suspended upon the crank shaft. The weight of the handle 27 and its parts retains the same in pendant relation and overcomes the frictional contact of the jaws 10 and 18 against-the sides of the crank shaft. It, is thus seen that by revolving the crank shaft a number of times by hand, when this tool is applied thereto, that the raised surface portions of the crank pin are readily ground off and that the'crank shaft is trued,

. It is of course understood that various changes and modifications may be made in the details of construction and design of the above specifically described embodiment of this invention without departing from the spirit thereof, and being restricted only by the scope of the following claims.

I claim: r

1. In a tool for truin'g shafts, the combination of a jaw unit including a j aw'adapted to engage against one side of a crank shaft, a second jaw slidable upon the unit for engagement against the opposite side of r the shaft, means for yildingly urging said jaws together, a cutter mounted in the second 80 jaw, means for normally urging the cutter from contact with the crank shaft, and independent means carried by the first jaw engaging the cutter for positivel advancing the same against the crank shat interposed between the jaws. v

2. In a tool for truing shafts,'the com bination of supporting jaws, means for hold ing the jaws to a shaft, a cutter carried by one jaw, independent yieldable means normally urging the cutter away from the shaft, and independent advancing means operable between another jaw and cutter for advancing the latter against the shaft.

3. In a tool for truing shafts, the combination of a pair of jaws, means for yieldingly compressing the jaws against the opposite sides of a crank shaft, a cutter slidably mounted in one of said jaws, and an independent adjustable connection between 100 the opposite jaw and said cutter for maintaining the cutter in predetermined spaced relation from said opposite jaw. I

4. In a tool for trning crank shafts, the combination of a pair of jaws, means for 1 5 yieldinglybinding the jaws against a shaft,

a cutter in one jaw, independent'means for advancing-the cutter against the shaft, said independent means being yieldable and ad justable to vary the position and-tension of 110 the cutter relatively to the crank shaft irrespec'tive of the clamping of the jaws. v

5. In a tool for truing shafts, the combination of-a pair of jaws, spring means connecting the jaws and adapted to bind 115 the same against the opposite sides of a shaft, a cutter slidably mounted in one of said jaws, independent spring means he'- tween the cutter and said jaw for urging the cutter out of contact with the shaft, and a 120 positive. adjustable connection between the opposite jaw and said cutter for advancing the latter toward the shaft against the ten sion of said spring means.

6. In a tool for truing shafts, the corh- 25 binationof a pair of jaws, means for yieldingly urging the jaws against the opposite sides of'a shaft, a cutter movably mounted in one of saidjaws, a spring carried by said ter outwardly from the jaw, and an adjust able --onnection between the opposite jaw and -uld. cutter for advancing the cutter inwardly through the jaw.

7. In a tool for truing' shafts, the c01nbination of a pair of jaws, means for yield ingly holding the jaws against the opposite sides of a shaft, one of said jaws being provided with a recess of greater depth than the diameter of a shaft to be engaged by the jaws and having opposed inclined faces spaced apart a distance less than the dia1neter of said shaft, and a cutter ar 'anged in the inner wall of the recess adapted to engage high portions of the shaft as the latter turns between said faces of the jaw, said faces being adapted to retain the shaft from following the cutter when a depressed side Ofthe shaft is presented to the cutter.

8. In a tool for truing shafts, the combination of a main jaw, a connecting plate slidably mounted upon. the outer end of the jaw, a second jaw. links connecting the second jaw to said slidable plate, a handle adjustably mounted on the slidable plate, a spring arranged between the handle and. said main jaw to urge the latter toward the second jaw, a. cutter slidably mounted in the main jaw, a stem for the cutter projecting into the handle, a spring in the handle engaging the stem for retracting the cutter through the main jaw, and a setscrew carried in the outer end of the handle and adapted to engage said stem to urge the same toward the main jaw against the tension of said second sprin 9. In a tool for truing shafts, the 00111- bination of a main jaw, a hollow shank projet-ting outwardly from the jaw, a second jaw, a pair of links detachably connected to the opposite ends of the second jaw, a con necting element slidable upon said shank and adapted to detachably engage thev free ends of said links, a handle adjustably connected to said connecting element and surrounding said shank, a spring interposed between the handle and the shank for urging the latter and the main jaw toward said second jaw, a stem slidable in the shank, a knife mounted upon the inner end of the stem and seated in the inner face of said main jaw, a spring arranged between the shank and the stem for normally urging the latter outwardly, and a set-screw carried by the handle and engaging the outer end of the stem for positivelyretaining the same I from outward inoven'ient with respect tothe handle and and second aw.

PIERRE SGHO'N. 

